N-related greenhouse gases in North America: innovations for a sustainable future

Agriculture contributes about 70-75% of Canadian and US anthropogenic emissions of nitrous oxide (N2O). Although progress has been made in recent decades to improve nitrogen use efficiency (NUE) in North America, including a decrease in N2O emissions per kilogram of harvested grain, significant technological, economic, and social impediments remain for further progress. A consensus has emerged for the need to foster partnerships to promote NUE research, extension, implementation, and performance indicators that encompass technical, social, and economic drivers of nutrient management. Recent innovative approaches include market trading, supply chain incentives, and consumer awareness. North America is a test bed for achieving greenhouse gas reduction and sustainability targets through voluntary private and public sector partnerships among growers, retailers, industry, scientists, regulators, and NGOs.